Spread spectrum systems are well-known since long and have been described in numerous articles and handbooks, such as in a basic article describing a system implementing a direct-sequence spread spectrum system, "A Communication Technique for Multipath Channels", R. Price et al., Proc. of the IRE Vol. 46, March 1958, pp. 555-570, a tutorial article "Theory of Spread-Spectrum Communications--A Tutorial", R. L. Pickholtz et al, IEEE Tr. on Comm., Vol. COM-30, No. 5, May 1982, pp. 855-884, and a handbook "Digital Communications", J. Proakis, McGraw-Hill, 1989, Chapters 7 and 8. In Chapter 7, pp. 702-799 of said handbook digital signalling over fading multipath channels is described as is the case in a mobile radio system, and in Chapter 8 spread-spectrum receivers, especially pp. 802-804, describing direct-sequence spread spectrum, pp. 831-836 describing PN (Pseudo-Noise) sequences for DS SS, pp. 862-864. The pseudo-noise sequence is generated using a linear feedback shift register. The maximum length of the pseudo-noise sequence is n=2.sup.m -1 bits, m being the number of shift register stages, and n being the period of the sequence. In a direct-sequence spread spectrum mobile radio system data to be transmitted are encoded using such pseudo-noise sequences. At reception side the data are decoded using correlation techniques. In known direct-sequence spread spectrum mobile radio systems for each channel, either a control channel or a traffic channel, a different short pseudo-noise sequence is used, the sequences preferably being orthogonal with respect to each other. In such a system, the data to be transmitted by the radio base station for instance are encoded using a chip-sequence of length n, and the data are decoded by the mobile radio station using a correlator with correlation window of length M. A pseudo-noise sequence typically is short when M&gt;n. A chip is a time duration of a rectangular pulse corresponding to the reciprocal of the available bandwidth. In practical systems the so-called chip rate is a multiple of the information rate of data to be transmitted. When applying such short pseudo-noise sequences at reception side there will be no problem to decode the data. On the other hand, for each channel a different pseudo-noise sequence has to be generated. In particular in mobile radio systems with many subscribers per cell such generation of many different pseudo-noise sequences is cumbersome.